2004 INFINITI QX56 ignition

PRECAUTIONS
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Use approved bonding agent, sealants or their equivalents when required.

Use hand tools, power tools (disassembly only) and recom-
mended special tools where specified for safe and efficient ser-
vice repairs.

When repairing the fuel, oil, water, vacuum or exhaust systems,
check all affected lines for leaks.

Before servicing the vehicle:
Protect fenders, upholstery and carpeting with appropriate cov-
ers.
Take caution that keys, buckles or buttons do not scratch paint.
WA RN ING:
To prevent ECM from storing the diagnostic trouble codes, do not carelessly disconnect the harness
connectors which are related to the engine control system and TCM (transmission control module)
system. The connectors should be disconnected only when working according to the WORK FLOW of
TROUBLE DIAGNOSES in EC and AT sections.
Precautions for Three Way CatalystEAS00149
If a large amount of unburned fuel flows into the catalyst, the catalyst temperature will be excessively high. To
prevent this, follow the instructions.

Use unleaded gasoline only. Leaded gasoline will seriously damage the three way catalyst.

When checking for ignition spark or measuring engine compression, make tests quickly and only when
necessary.

Do not run engine when the fuel tank level is low, otherwise the engine may misfire, causing damage to
the catalyst.
Do not place the vehicle on flammable material. Keep flammable material off the exhaust pipe and the three
way catalyst.
Precautions for Fuel (Unleaded Premium Gasoline Required)EAS001KH
Use unleaded premium gasoline with an octane rating of at least 91 AKI (Anti-Knock Index) number (Research
octane number 96).
If unleaded premium gasoline is not available, unleaded regular gasoline with an octane rating of at least 87
AKI number (Research octane number 91) can be used, but only under the following precautions:

have the fuel tank filled only partially with unleaded regular gasoline, and fill up with unleaded premium
gasoline as soon as possible.

avoid full throttle driving and abrupt acceleration.
However, for maximum vehicle performance, the use of unleaded premium gasoline is recommended.
CAUTION:
Do not use leaded gasoline. Using leaded gasoline will damage the three way catalyst. Do not use E-85
fuel (85% fuel ethanol, 15% unleaded gasoline) unless the vehicle is specifically designed for E-85 fuel
PBIC0190E
SGI234

GI-6
PRECAUTIONS
Revision: August 20072004 QX56
(i.e. Flexible Fuel Vehicle - FFV models). Using a fuel other than that specified could adversely affect
the emission control devices and systems, and could also affect the warranty coverage validity.
Precautions for Multiport Fuel Injection System or Engine Control SystemEAS0014B

Before connecting or disconnecting any harness connector for
the multiport fuel injection system or ECM:
Turn ignition switch to “OFF” position.
Disconnect negative battery terminal.
Otherwise, there may be damage to ECM.

Before disconnecting pressurized fuel line from fuel pump to
injectors, be sure to release fuel pressure.

Be careful not to jar components such as ECM and mass air
flow sensor.
Precautions for HosesEAS0014C
HOSE REMOVAL AND INSTALLATION

To prevent damage to rubber hose, do not pry off rubber hose
with tapered tool or screwdriver.

To reinstall the rubber hose securely, make sure of hose inser-
tion length and clamp orientation. (If tube is equipped with hose
stopper, insert rubber hose into tube until it butts up against
hose stopper.)
HOSE CLAMPING

If old rubber hose is re-used, install hose clamp in its original
position (at the indentation where the old clamp was). If there is
a trace of tube bulging left on the old rubber hose, align rubber
hose at that position.

Discard old clamps; replace with new ones.
SGI787
SM A01 9D
SM A02 0D
SM A02 1D

HOW TO USE THIS MANUAL
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How to Follow Trouble DiagnosesEAS0014K
DESCRIPTION
NOTICE:
Trouble diagnoses indicate work procedures required to diagnose problems effectively. Observe the following
instructions before diagnosing.
1.Before performing trouble diagnoses, read the “Preliminary Check”, the “Symptom Chart” or the
“Work Flow”.
2.After repairs, re-check that the problem has been completely eliminated.
3.Refer to Component Parts and Harness Connector Location for the Systems described in each
section for identification/location of components and harness connectors.
4.Refer to the Circuit Diagram for quick pinpoint check.
If you need to check circuit continuity between harness connectors in more detail, such as when a
sub-harness is used, refer to Wiring Diagram in each individual section and Harness Layout in PG
section for identification of harness connectors.
5.When checking circuit continuity, ignition switch should be OFF.
6.Before checking voltage at connectors, check battery voltage.
7.After accomplishing the Diagnostic Procedures and Electrical Components Inspection, make sure
that all harness connectors are reconnected as they were.
HOW TO FOLLOW TEST GROUPS IN TROUBLE DIAGNOSES
1.Work and diagnostic procedure
Start to diagnose a problem using procedures indicated in enclosed test groups.
2.Questions and required results
Questions and required results are indicated in bold type in test group.
The meaning of are as follows:
SAIA0256E

HOW TO USE THIS MANUAL
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Harness Indication

Letter designations next to test meter probe indicate harness
(connector) wire color.

Connector numbers in a single circle M33 indicate harness con-
nectors.
Component Indication
Connector numbers in a double circle F211 indicate component connectors.
Switch Positions
Switches are shown in wiring diagrams as if the vehicle is in the “normal” condition.
A vehicle is in the “normal” condition when:

ignition switch is “OFF”,

doors, hood and trunk lid/back door are closed,

pedals are not depressed, and

parking brake is released.
Detectable Lines and Non-Detectable Lines
In some wiring diagrams, two kinds of lines, representing wires, with different weight are used.
AGI070
SGI860

SERVICE INFORMATION FOR ELECTRICAL INCIDENT
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VOLTAGE CHECK METHOD
To help in understanding the diagnosis of open circuits please refer to the previous schematic.
In any powered circuit, an open can be found by methodically checking the system for the presence of voltage.
This is done by switching the DMM to the voltage function.

Connect one probe of the DMM to a known good ground.

Begin probing at one end of the circuit and work your way to the other end.

With SW1 open, probe at SW1 to check for voltage.
voltage; open is further down the circuit than SW1.
no voltage; open is between fuse block and SW1 (point A).

Close SW1 and probe at relay.
voltage; open is further down the circuit than the relay.
no voltage; open is between SW1 and relay (point B).

Close the relay and probe at the solenoid.
voltage; open is further down the circuit than the solenoid.
no voltage; open is between relay and solenoid (point C).
Any powered circuit can be diagnosed using the approach in the previous example.
Testing for “Shorts” in the Circuit
To simplify the discussion of shorts in the system, please refer to the following schematic.
RESISTANCE CHECK METHOD

Disconnect the battery negative cable and remove the blown fuse.

Disconnect all loads (SW1 open, relay disconnected and solenoid disconnected) powered through the
fuse.

Connect one probe of the DMM to the load side of the fuse terminal. Connect the other probe to a known
good ground.

With SW1 open, check for continuity.
continuity; short is between fuse terminal and SW1 (point A).
no continuity; short is further down the circuit than SW1.

Close SW1 and disconnect the relay. Put probes at the load side of fuse terminal and a known good
ground. Then, check for continuity.
continuity; short is between SW1 and the relay (point B).
no continuity; short is further down the circuit than the relay.

Close SW1 and jump the relay contacts with jumper wire. Put probes at the load side of fuse terminal and
a known good ground. Then, check for continuity.
continuity; short is between relay and solenoid (point C).
no continuity; check solenoid, retrace steps.
VOLTAGE CHECK METHOD

Remove the blown fuse and disconnect all loads (i.e. SW1 open, relay disconnected and solenoid discon-
nected) powered through the fuse.

Turn the ignition key to the ON or START position. Verify battery voltage at the battery + side of the fuse
terminal (one lead on the battery + terminal side of the fuse block and one lead on a known good ground).

With SW1 open and the DMM leads across both fuse terminals, check for voltage.
voltage; short is between fuse block and SW1 (point A).
SG I8 47 -A

CONSULT-II CHECKING SYSTEM
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CONSULT-II CHECKING SYSTEMPFP:00000
DescriptionEAS001SK

CONSULT-II is a hand-held type tester. When it is connected with a diagnostic connector equipped on the
vehicle side, it will communicate with the control unit equipped in the vehicle and then enable various
kinds of diagnostic tests.

Refer to "CONSULT-II Operator's Manual" for more information.
Function and System ApplicationEAS001SL
x: Applicable.
*1: IVIS (NATS) [INFINITI Vehicle Immobilizer System (Nissan Anti-Theft System)].
*2: This system is shown with IVIS (NATS) using program card AEN04A-1 or later.Diagnostic test
modeFunction
ENGINE
A/T
ALL MODE AWD/4WD
ICC
ABS
AIR BAG
IPDM E/R
BCM
AUTO DRIVE POS.
REARVIEW CAMERA
AIR LEVELIZER
IVIS (NATS)
*1
IVIS (NATS BCM OR S/ENT)
*1
Work supportThis mode enables a technician to adjust some
devices faster and more accurately by following the
indications on CONSULT-II.x - xxx - - xxxx - -
Self-diagnosticSelf-diagnostic can be performed quickly. -----x-------
Self-diagnos-
tic resultsSelf-diagnostic results can be read and erased
quickly.xxxxx - xxx - xxx
Trouble diag-
nostic recordCurrent self-diagnostic results and all trouble diagnos-
tic records previously stored can be read.----- x-------
Data monitor Input/Output data in the ECM can be read. xxxxx - x - xxx - -
Data monitor
(spec)Data monitor specification can be read. x------------
CAN diagno-
sis support
monitorThe communication condition of CAN communication
line can be read.xxxxx - xxx - - - -
Active testDiagnostic Test Mode in which CONSULT-II drives
some actuators apart from the ECMs and also shifts
some parameters in a specified range.x- - xx- x- xxx- -
Function testThis mode can show results of self-diagnosis of ECU
with either “OK” or “NG”. For engines, more practical
tests regarding sensors/switches and/or actuators are
available.xx - - xx - -- - -- -
DTC & SRT
confirmationThe results of SRT (System Readiness Test) and the
self-diagnosis status/result can be confirmed.x------------
DTC work sup-
portThe operating condition to confirm Diagnosis Trouble
Codes can be selected.xx-----------
ECM/ECU part
numberECM/ECU part number can be read. xxxxx - -xx xx - -
ECU discrimi-
nated No.Classification number of a replacement ECU can be
read to prevent an incorrect ECU from being installed.-----x-------
Configuration ECM checks its own NATS communication interface. -------x-----
PIN read
*2This mode shows the BCM-specific 5-digit code. ------------x
Control unit
initialization
*2All registered ignition key IDs in NATS components
can be initialized and new IDs can be registered.-----------x-

GI-38
CONSULT-II CHECKING SYSTEM
Revision: August 20072004 QX56
Nickel Metal Hydride Battery Replacement EAS0014S
CONSULT-II contains a nickel metal hydride battery. When replacing the battery obey the following:
WAR NIN G:
Replace the nickel metal hydride battery with Genuine CONSULT-II battery only. Use of another bat-
tery may present a risk of fire or explosion. The battery may present a fire or chemical burn hazard if
mistreated. Do not recharge, disassemble or dispose of in fire.
Keep the battery out of reach of children and discard used battery conforming to the local regulations.
Checking EquipmentEAS0014T
When ordering the below equipment, contact your NISSAN distributor.
CAUTION:

Previous CONSULT-II “I” and “Y” DLC-I and DLC-II cables should NOT be used anymore because
their DDL connector pins can be damaged during cable swapping.

If CONSULT-II is used with no connection of CONSULT-II CONVERTER, malfunctions might be
detected in self- diagnosis depending on control unit which carries out CAN communication.

If CONSULT-II CONVERTER is not connected with CONSULT-II, the vehicle enters “FAIL SAFE
MODE” which will “LIGHT UP the HEAD LIGHT” and /or “COOLING FAN ROTATING” when CON-
SULT-II is started.
NOTE:

The CONSULT-II must be used in conjunction with a program card.
CONSULT-II does not require loading (Initialization) procedure.

Be sure the CONSULT-II is turned OFF before installing or removing a program card.
CONSULT-II Start ProcedureEAS0014U
NOTE:
Turning ignition switch off when performing CAN diagnosis could cause CAN memory to be erased.
1. Connect CONSULT-II and CONSULT-II CONVERTER to the
data link connector.
Tool name Description
NISSAN CONSULT-II (J-44200)
1. CONSULT-II unit (Tester internal soft: Resident
Version 3.4.0) and accessories.
2. Program card UED04D-1 and AEN04A-1 (for
NATS) or later, to confirm the best combination
of these software, refer to CONSULT-II Opera-
tion Manual.
3. CONSULT-II CONVERTER.
4. "CONSULT-II pigtail" cable.
SAIA0363E
PAIA0070E

CONSULT-II CHECKING SYSTEM
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2. If necessary, turn on the ignition switch.
3. Touch “START (NISSAN BASED VHCL)” or System Shortcut
key (eg: ENGINE) on the screen.
CONSULT-II Data Link Connector (DLC) CircuitEAS001SM
INSPECTION PROCEDURE
If the CONSULT-II cannot diagnose the system properly, check the following items:
NOTE:
The preceding schematic is an example and may not be a true representation of the vehicle. The actual DDL1
circuits (CAN lines) from DLC pins 6 and 14 as well as the DDL2 circuit (K-line) from DLC pin 7 may be con-
nected to more than one system. A short in a DDL circuit connected to a control unit in one system may affect
CONSULT-II access to other systems.
BCIA0029E
LAIA0028E
Symptom Check item
CONSULT-II cannot access
any system.

CONSULT-II DLC power supply circuit (Terminal 8) and ground circuit (Terminal 4). For detailed cir-
cuit, refer to LAN-5, "
CAN Communication Unit" .

CONSULT-II DLC cable and CONSULT-II CONVERTER.
CONSULT-II cannot access
individual system. (Other sys-
tems can be accessed.)

CONSULT-II program card (Check the appropriate CONSULT-II program card for the system.
Refer to GI-38, "
Checking Equipment" .

Power supply and ground circuit for the control unit of the system (For detailed circuit, refer to wir-
ing diagram for each system.)

Open or short circuit between the system and CONSULT-II DLC (For detailed circuit, refer to wiring
diagram for each system.)

Open or short circuit in CAN or K communication line. Refer to LAN-3, "Precautions When Using
CONSULT-II" .